The present invention relates to a rubber composition for a base tread and a tire comprising the same.
Recently, for the purpose of energy saving, various means have been applied to reducing rolling resistance of a tire (for improving rolling resistance properties) or improving steering stability of a car. An example of the means is using a rubber composition exhibiting excellent rolling resistance properties and steering stability at an inner side layer of a base tread which has two layer structure (an inner layer and a surface layer).
A rubber composition for a tire containing a polybutadiene rubber having 1 to 25% of a 1,2-syndiotactic polybutadiene crystal as a rubber component is disclosed in the Japanese Unexamined Patent Publication No. 11-349732, but if the rubber composition is used as a base tread, there has been a problem that both of steering properties mainly related to rigidity and tan δ related to rolling resistance can not be satisfied.